I agree that a lot of O'Sensei's guys bail out in some of them but perhaps it might have something to do with how hard they are going to get hit or hit the ground if they don't pre-empt. I think during the Hell dojo days they probably develop a set of skills to keep from getting injured. I believe Saotome commented once that he was thrown so hard he broke his shoulder. Self-preservation. ONe of the uke's from Japan for my instructor says he bails because sensei is dangerous. If he doesn't, he risk getting injured.

Mike, is the bounce a form of grounding? Directing the energy to ground and then sending it back through the center?